Various styles of power driven meat cutting tools have been devised wherein a power driven ring blade is rotatably mounted on a holder which in turn is mounted on a manually operated handpiece having a handle at one end thereof which is gripped and manipulated by an operator. These tools have been used for some time to facilitate the removal of meat from a carcass, primarily in a trimming operation or for removing the meat remains from the bones of an animal. These meat cutting tools are either electrically driven or pneumatic driven. Some examples of such electric meat cutting tools are shown in U.S. Pat. Nos. 3,024,532; 3,269,010; 3,461,557; 3,605,841; 4,494,311; and 4,575,938.
These electrically driven tools generally consist of a tubular shaped handpiece having a rear handle portion and a front body portion, with an annular blade holder being attached to the front portion of the handpiece with a ring blade being removably mounted thereon by various mounting arrangements. The blade is formed with gear teeth which are in driving engagement with the pinion gear mounted within the end of the handpiece. A flexible cable extends from a motor located adjacent to the work area and enters the rear of the handle and extends therethrough and is connected by a driving connection to the pinion gear. The cable is surrounded by a flexible casing which terminates within the handpiece or tubular body at a ferrel or similar connector.
Although these prior handpieces perform satisfactorily, it is desirable that as much comfort as possible be provided for the operator of the trimming knives. These knives are used in a cold environment over prolonged periods of time and ultimately results in fatigue to the hand of the operator thereby resulting in lower production. Furthermore, these trimming knives, and in particular the handle portions thereof, become coated with grease and slippery meat particles from the animal carcasses being trimmed making the handles difficult to grip requiring a greater pressure to be exerted thereon by the operator to insure a tight grip and to prevent the handpiece from turning in the operator's hand. The handpieces have a natural tendency to rotate in the operator's hand due to the natural rotational force of the rotating blade cutting into the meat causing an opposite twisting and turning reaction on the handle. As a consequence, the operator grips the handpiece even tighter to prevent this counter rotation and to overcome the slipperiness caused by the accumulating meat particles and grease on the handpiece which makes it still more difficult to grip the handpiece satisfactory. Likewise, it is desirable to increase the safety of the handpieces in any way possible and prevent or materially reduce the possibility of injury to an operator thereof.
Prior handles for such meat trimming knives have a relatively uniform cylindrical shape which are bulky and difficult for the operator to firmly grip over an extended period of time thereby increasing the fatigue on the operator's hand. Furthermore, it is difficult to provide a separate covering for the handpiece, such a rubber covering, to reduce the fatigue on the operator's hand since such coverings are subject to the accumulation of meat particles and grease making them difficult to clean for maintaining the required sanitary condition for the knives.
Other meat trimming knives such as shown in U.K. Pat. No. 679,236 and U.S. Pat. Nos. 2,766,524; 3,176,397; and 3,605,841 are formed with either a series of grooves or raised ribs extending axially along the handle or in a circular fashion thereabout to attempt to improve the operator's grip on the handle to reduce slippage and fatigue. Others have tried to increase the gripping effectiveness of the knife handle by placing a series of drilled holes throughout the handpiece or providing a knurled gripping surfaces. However, these increase considerably the difficulty of maintaining the cleanliness of the knife due to the difficulty of removing the trapped meat particles and grease from the holes and knurled surface at the end of each work period. Furthermore, these recesses and holes become quickly filled with the meat particles and grease reducing their effectiveness.
Therefore the need has existed for an improved handle for the handpiece of a meat trimming knife which reduces the fatigue on the operator's hand by providing a more comfortable handle contour and by reducing the accumulation of meat particles and grease which heretofore necessitated an increase in the operator's gripping of the handle to prevent rotation of the handle during operation of the trimming knife.